Integrated Circuit Devices and Methods of Manufacturing the Same

ABSTRACT

An integrated circuit device may include a substrate including a main surface, a compound semiconductor nanowire extending from the main surface in a first direction perpendicular to the main surface and including a first section and a second section alternately arranged in the first direction, a gate electrode covering the first section, and a gate dielectric layer between the first section and the gate electrode. The first section and the second section may have the same composition as each other and may have different crystal phases from each other

CROSS-REFERENCE TO RELATED APPLICATION

This U.S. non-provisional application claims priority under 35 U.S.C.§119 to Korean Patent Application No. 10-2016-0064936, filed on May 26,2016, in the Korean Intellectual Property Office, the entire content ofwhich is incorporated by reference herein.

BACKGROUND

The inventive concepts relate to integrated circuit devices and methodsof manufacturing the same, and, more particularly, to integrated circuitdevices including a compound semiconductor nanowire and methods ofmanufacturing the same.

As the integration density of semiconductor devices increases, therehave been efforts to improve the performance of transistors by usingvarious materials such as strained channels, high-k dielectric layers,and metal gates. However, as the gate length of transistors graduallydecreases, the reliability and performance of integrated circuit devicesutilizing these transistors can be affected.

SUMMARY

The inventive concepts provide integrated circuit devices capable ofrealizing high reliability and performance by providing transistorshaving a precisely controlled gate length.

The inventive concepts also provide methods of manufacturing integratedcircuit devices, whereby a transistor having a precisely controlled gatelength may be manufactured through a low-cost, simple process.

According to an aspect of the inventive concepts, an integrated circuitdevice may include a substrate including a main surface a compoundsemiconductor nanowire extending from the main surface in a firstdirection perpendicular to the main surface and including a firstsection and a second section alternately arranged in the firstdirection, a gate electrode covering the first section, and a gatedielectric layer between the first section and the gate electrode. Thefirst section and the second section have the same composition as eachother and have different crystal phases from each other.

According to another aspect of the inventive concepts, a method ofmanufacturing an integrated circuit device may include forming acompound semiconductor nanowire extending from a main surface of asubstrate in a first direction perpendicular to the main surface andcomprising a first section and a pair of second sections alternatelyarranged in the first direction so that respective ones of the pair ofsecond sections adjoin both ends of the first section, with the firstsection between the respective ones of the pair of second sections,decreasing a width of the first section by selectively etching the firstsection from among the first section and the pair of second section inthe compound semiconductor nanowire and preparing a space having avertical length limited by the respective ones of the pair of secondsections, and forming a gate dielectric layer and a gate electrode inthe space. The first section and the second section have the samecomposition as each other and have different crystal phases from eachother.

According to another aspect of the inventive concepts, an integratedcircuit device may include a substrate with a main surface, a compoundsemiconductor nanowire extending from the main surface in a firstdirection perpendicular to the main surface and including a lower secondsection, a first section on the lower second section, and an uppersecond section on the first section, and a gate electrode on the firstsection. A portion of the gate electrode may be between, in the firstdirection, the upper second section and the lower second section. Thefirst section may have a different crystal phase from the upper secondsection and the lower second section.

BRIEF DESCRIPTION OF THE DRAWINGS

Embodiments of the inventive concepts will be more clearly understoodfrom the following detailed description taken in conjunction with theaccompanying drawings in which:

FIG. 1 is a cross-sectional view of configurations of an integratedcircuit device according to embodiments of the inventive concepts;

FIGS. 2A to 2C are cross-sectional views of various modified exampleconfigurations of an integrated circuit device taken along line II-II′of FIG. 1, according to example embodiments of the inventive concepts;

FIG. 3 is a cross-sectional view of configurations of an integratedcircuit device according to other embodiments of the inventive concepts;

FIG. 4 is a cross-sectional view of configurations of an integratedcircuit device according to other embodiments of the inventive concepts;

FIG. 5 is a cross-sectional view of configurations of an integratedcircuit device according to other embodiments of the inventive concepts;

FIG. 6 is a cross-sectional view of configurations of an integratedcircuit device according to other embodiments of the inventive concepts;

FIGS. 7A to 7C are diagrams of an integrated circuit device according toother embodiments of the inventive concepts, wherein FIG. 7A is a layoutof configurations of the integrated circuit device, FIG. 7B is across-sectional view taken along line B-B′ of FIG. 7A, and FIG. 7C is across-sectional view taken along line C-C′ of FIG. 7A;

FIGS. 8A to 8I are cross-sectional views illustrating methods ofmanufacturing integrated circuit devices according to embodiments of theinventive concepts;

FIGS. 9A and 9B are cross-sectional views illustrating methods ofmanufacturing integrated circuit devices according to other embodimentsof the inventive concepts;

FIGS. 10A to 15B are cross-sectional views illustrating methods ofmanufacturing integrated circuit devices according to other embodimentsof the inventive concepts, wherein FIGS. 10A, 11A, . . . , 15A arecross-sectional views of a portion corresponding to a cross-sectiontaken along line B-B′ of FIG. 7A, and FIGS. 10B, 11B, . . . , 15B arecross-sectional views of a portion corresponding to a cross-sectiontaken along line C-C′ of FIG. 7A; and

FIG. 16 is a block diagram of an electronic system including anintegrated circuit device according to embodiments of the inventiveconcepts.

DETAILED DESCRIPTION

Hereinafter, embodiments will be described in detail with reference tothe accompanying drawings. Like reference numerals in the drawingsdenote like elements throughout, and a repeated description thereof willbe omitted.

FIG. 1 is a cross-sectional view of configurations of an integratedcircuit device 100 according to embodiments of the inventive concepts.

Referring to FIG. 1, the integrated circuit device 100 may include asubstrate 110 having a main surface 110M, and a compound semiconductornanowire 120 extending from the main surface 110M of the substrate 110in a first direction (e.g., direction Z) perpendicular to the mainsurface 110M. The term “nanowire” used herein may refer to athree-dimensional structure having a diameter of about 10 nm or less.

The main surface 110M of the substrate 110 may have a {111} crystalplane.

The compound semiconductor nanowire 120 may have a structure in which afirst section 122 and a second section 126 are alternately arranged onthe substrate 110 in the first direction (e.g., direction Z). In someembodiments, a pair of second sections 126 may respectively adjoin bothends of the first section 122 with the first section 122 in the middle.The first section 122 and the second section 126 may have the samecomposition as each other and may have different crystal phases fromeach other.

The compound semiconductor nanowire 120 may include a Group III-Vmaterial. In some embodiments, the compound semiconductor nanowire 120may include a compound semiconductor that includes at least one ofindium (In), gallium (Ga), and aluminum (Al) as a Group III element andat least one of arsenic (As), phosphorus (P), and antimony (Sb) as aGroup V element. The first section 122 and the second section 126 mayinclude Group III-V materials having the same composition as each otherbut may have different crystal phases from each other.

The compound semiconductor nanowire 120 may have a crystal phasesuperstructure in which a zinc-blende (ZB) crystal phase and a wurtzite(WZ) crystal phase are alternately and regularly arranged. In someembodiments, the first section 122 and the second section 126 may havedifferent crystal phases from each other, and the crystal phases may beselected from the ZB crystal phase and the WZ crystal phase. In someembodiments, the first section 122 may have the WZ crystal phase, andthe second section 126 may have the ZB crystal phase. In otherembodiments, the first section 122 may have the ZB crystal phase, andthe second section 126 may have the WZ crystal phase.

In some embodiments of the inventive concepts, the compoundsemiconductor nanowire 120 may include, for example, GaAs, GaP, InP,InAs, InSb, GaSb, InGaP, InGaAs, InGaSb, GaAsSb, and/or GaAsP.

Although FIG. 1 illustrates the compound semiconductor nanowire 120including one first section 122 and a pair of second sections 126 thatrespectively adjoin both ends of the first section 122 with the firstsection 122 in the middle, the inventive concepts are not limitedthereto. For example, the compound semiconductor nanowire 120 mayinclude a plurality of first sections 122 and a plurality of secondsections 126, and the plurality of first sections 122 and the pluralityof second sections 126 may be alternately arranged in a length directionof the compound semiconductor nanowire 120 (e.g., direction Z).

In the compound semiconductor nanowire 120, the first section 122 mayhave a first width W1 in a second direction parallel to the main surface110M of the substrate 110 (e.g., in direction X). In addition, thesecond section 126 may have a second width W2 in the second direction,the second width W2 being greater than the first width W1. In someembodiments, the first width W1 may be about 5 to 10 nm, but theinventive concepts are not limited thereto.

A gate electrode GE1 surrounding the first section 122 may be formed ina peripheral region of the first section 122. In the compoundsemiconductor nanowire 120, a gate dielectric layer 134 may be disposedbetween the first section 122 and the gate electrode GE1. The firstsection 122 may provide a vertical channel region CH1 of a transistorTR1 including the gate electrode GE1.

FIGS. 2A to 2C are cross-sectional views of various modified exampleconfigurations of an integrated circuit device 100 taken along lineII-II′ of FIG. 1, according to example embodiments of the inventiveconcepts.

In some embodiments, as illustrated in FIG. 2A, a cross-section of thefirst section 122 providing the vertical channel region CH1 of thetransistor TR1 in the integrated circuit device 100 may have a circularshape. Accordingly, cross-sections of the gate dielectric layer 134 andthe gate electrode GE1 that surround the first section 122 may each havean annular shape, and thus, a transistor that has a gate-all-around(GAA) structure may be provided.

In some embodiments, as illustrated in FIGS. 2B and 2C, a cross-sectionof the first section 122 providing the vertical channel region CH1 ofthe transistor TR1 in the integrated circuit device 100 may have varioushexagon shapes. Accordingly, the gate dielectric layer 134 and the gateelectrode GE1 that surround the first section 122 may each have ahexagon cross-section shape that corresponds to the cross-section shapeof the first section 122, and thus, a transistor that has a GAAstructure may be provided.

Although FIGS. 2A to 2C illustrate cases in which a cross-section of thefirst section 122 providing the vertical channel region CH1 has acircular or hexagonal shape, the inventive concepts are not limitedthereto. For example, the cross-section of first section 122 may havevarious polygonal shapes such as, for example, a quadrangle, or may havean oval shape.

Referring to FIG. 1 again, the substrate 110 may include a source region110S that is formed in the substrate 110 from the main surface 110M. Thesource region 110S may include an impurity region doped with a firstdopant.

A drain region 126D may be formed in at least a portion of a secondsection 126, from among a plurality of second sections 126 included inthe compound semiconductor nanowire 120. In some embodiments, the drainregion 126D may be formed in a second section 126, from among theplurality of second sections 126, that is separated from the substrate110 by at least one first section 122. The drain region 126D may includean impurity region doped with a second dopant.

In some embodiments, each of the source region 110S and the drain region126D may include an impurity region that has a doping concentration ofabout 10¹⁷ atom/cm³ or greater, but the inventive concepts are notlimited thereto. In some embodiments, the source region 110S and thedrain region 126D may be N-type doping regions or P-type doping regions.

The first dopant used for doping the source region 110S and the seconddopant used for doping the drain region 126D may be variously selectedaccording to respective composition materials of the substrate 110 andthe second section 126. In some embodiments, according to the respectivecomposition materials of the substrate 110 and the second section 126,the first dopant and the second dopant may each be selected fromelements that may serve as a donor or an acceptor, for example, Be, Mg,Zn, Cd, C, Si, Ge, Sn, S, Se, and/or Te.

In some embodiments, the first dopant in the source region 110S and thesecond dopant in the drain region 126D may include different elementsfrom each other. In some embodiments, the first dopant in the sourceregion 110S and the second dopant in the drain region 126D may includethe same element as each other.

In some embodiments, the first section 122 providing the verticalchannel region CH1 may have a doping type opposite to that in the sourceregion 110S and the drain region 126D. For example, when a doping typeof the source region 110S and the drain region 126D is N type, a dopingtype of the first section 122 may be P type. In some embodiments, whenthe doping type of the source region 110S and the drain region 126D is Ptype, the doping type of the first section 122 may be N type. In someembodiments, the first section 122 providing the vertical channel regionCH1 may include an undoped material.

The substrate 110 may include a semiconductor such as, for example,silicon (Si) or germanium (Ge), or a compound semiconductor such as, forexample, SiGe, SiC, GaAs, InAs, or InP. In some embodiments, thesubstrate 110 may include at least one of a Group III-V material and aGroup IV material. The Group III-V material may be a binary, ternary, orquaternary compound that includes at least one Group III element and atleast one Group V element. The Group III-V material may be a compoundthat includes at least one of In, Ga, and Al as a Group III element andat least one of As, P, and Sb as a Group V element. For example, theGroup III-V material may be selected from InP, In_(z)Ga_(1-z)As (0≦z≦1),and Al_(z)Ga_(1-z)As (0≦z≦1). The binary compound may be, for example,one of InP, GaAs, InAs, InSb, and GaSb. The ternary compound may be oneof InGaP, InGaAs, AlInAs, InGaSb, GaAsSb, and GaAsP. The Group IVmaterial may be Si or Ge. However, the Group III-V material and theGroup IV material that may be used in integrated circuit devicesaccording to one or more embodiments of the inventive concepts are notlimited to the above examples.

In some embodiments, the gate dielectric layer 134 may include aninterfacial layer that contacts the first section 122 providing thevertical channel region CH1, and a high-k dielectric layer that coversthe interfacial layer. The interfacial layer may be obtained byoxidizing a surface of the first section 122. The interfacial layer mayinclude a low-k dielectric material layer that has a dielectric constantof 9 or less, for example, a silicon oxide film, a silicon oxynitridefilm, a Ga oxide film, a Ge oxide film, or an oxide of a Group III-Vmaterial. In some embodiments, the interfacial layer may be omitted. Inthis case, the gate dielectric layer 134 may include only the high-kdielectric layer.

In some embodiments, the high-k dielectric layer constituting the gatedielectric layer 134 may include a material that has a dielectricconstant that is greater than that of the interfacial layer. Forexample, the high-k dielectric layer may have a dielectric constant ofabout 10 to 25. The high-k dielectric layer may include a materialselected from, for example, hafnium oxide, hafnium oxynitride, hafniumsilicon oxide, lanthanum oxide, lanthanum aluminum oxide, zirconiumoxide, zirconium silicon oxide, tantalum oxide, titanium oxide, bariumstrontium titanium oxide, barium titanium oxide, strontium titaniumoxide, yttrium oxide, aluminum oxide, lead scandium tantalum oxide, leadzinc niobate, and a combination thereof. However, a material of thehigh-k dielectric layer is not limited to the above examples.

The gate electrode GE1 may include a work function controllingmetal-containing layer. In some embodiments, the gate electrode GE1 mayfurther include a gap filling metal-containing layer that fills a gapformed in an upper portion of the work function controllingmetal-containing layer. In some embodiments, the gate electrode GE1 mayinclude a metal nitride layer and/or a metal layer. The metal nitridelayer and/or the metal layer may each include at least one metalselected from, for example, titanium (Ti), tungsten (W), ruthenium (Ru),niobium (Nb), molybdenum (Mo), hafnium (Hf), nickel (Ni), cobalt (Co),platinum (Pt), ytterbium (Yb), terbium (Tb), dysprosium (Dy), erbium(Er), and palladium (Pd). In some embodiments, the gate electrode GE1may include a stacked structure of TiAlC/TiN, a stacked structure ofTiN/TaN/TiAlC/TiN, or a stacked structure of TiN/TaN/TiN/TiAlC/TiN. Inthe above stacked structures, the TiAlC layer or the TiN layer may serveas the work function controlling metal-containing layer.

FIG. 3 is a cross-sectional view of configurations of an integratedcircuit device 100A according to other embodiments of the inventiveconcepts.

Referring to FIG. 3, the integrated circuit device 100A generally hasthe same configuration as those of the integrated circuit device 100illustrated in FIG. 1. However, the integrated circuit device 100A mayfurther include a wiring layer 150 that contacts the gate electrode GE1and extends parallel to the main surface 110M of the substrate 110 atsubstantially the same level as that of the first section 122 on thesubstrate 110. The wiring layer 150 may serve as a gate contact wiringlayer.

In a length direction of the compound semiconductor nanowire 120 (e.g.,direction Z), a first shortest distance L1 between the substrate 110 andthe gate electrode GE1 may be less than a second shortest distance L2between the substrate 110 and the wiring layer 150. A distancedifference ΔD1 between the first shortest distance L1 and the secondshortest distance L2 may be greater than 0. For example, the distancedifference ΔD1 may be about 0.1˜3 nm, but the inventive concepts are notlimited thereto.

In addition, in the length direction of the compound semiconductornanowire 120 (e.g., direction Z), the uppermost surface of the gateelectrode GE1 may be farther from the substrate 110 than the uppermostsurface of the wiring layer 150 is. A distance difference ΔD2 between asurface of the gate electrode GE1 that is farthest from the substrate110 (i.e., an uppermost surface of the gate electrode GE1) and a surfaceof the wiring layer 150 that is farthest from the substrate 110 (i.e.,an uppermost surface of the wiring layer 150) may be greater than 0. Forexample, the distance difference ΔD2 may be about 0.1˜3 nm, but theinventive concepts are not limited thereto.

Each of the distance differences ΔD1 and ΔD2 may have a value greaterthan 0 so that, in the length direction of the compound semiconductornanowire 120 (e.g., direction Z), a formation region of the wiring layer150 may not be out of a vertical length range of the gate electrode GE1(i.e., the length of the gate electrode GE1 in the Z direction). Thedistance differences ΔD1 and ΔD2 may provide an alignment margin betweenthe wiring layer 150 and the gate electrode GE1. That is, a processmargin for controlling a formation location of the wiring layer 150during a formation process of the wiring layer 150 may increase by asmuch as the distance differences ΔD1 and ΔD2.

In some embodiments, the wiring layer 150 may include a metal layer. Insome embodiments, the wiring layer 150 may have a stacked structureincluding a conductive barrier film and a metal layer. The conductivebarrier film may include, for example, TiN, TaN, AlN, WN, or acombination thereof. The metal layer may include, for example, W, Cu,Al, an alloy thereof, and/or a combination thereof. However, compositionmaterials of the conductive barrier film and the metal layer are notlimited to the above examples.

An insulation mask layer 112 and a lower insulation spacer 142 may besequentially stacked between the substrate 110 and the wiring layer 150.

The insulation mask layer 112 may cover a portion of a side wall of asecond section 126, from among the pair of second sections 126, that iscloser to the substrate 110. In some embodiments, the insulation masklayer 112 may include silicon nitride (SiN) and/or dioxide silicon(SiO₂), but a material of the insulation mask layer 112 is not limitedto the above examples.

The lower insulation spacer 142 may cover a portion of a lower side ofthe gate electrode GE1, a portion of the gate dielectric layer 134, anda side wall of the second section 126, from among the pair of secondsections 126 adjacent the first section 122, that is closer to thesubstrate 110.

An upper insulation spacer 152 may be on the wiring layer 150. The upperinsulation spacer 152 may cover a portion of an upper side of the gateelectrode GE1, a portion of the gate dielectric layer 134, and a sidewall of a second section 126, from among the pair of second sections 126adjacent the first section 122, that is farther from the substrate 110.

The wiring layer 150 may include a plate-type conductive layer thatextends parallel to the main surface 110M of the substrate 110 betweenthe lower insulation spacer 142 and the upper insulation spacer 152.

In some embodiments, each of the lower insulation spacer 142 and theupper insulation spacer 152 may include a material selected from, forexample, SiN, SiCN, SiOCN, SiO₂, and a combination thereof, but amaterial of each of the lower insulation spacer 142 and the upperinsulation spacer 152 is not limited to the above examples.

The integrated circuit devices 100 and 100A according to embodiments ofthe inventive concepts, described with reference to FIGS. 1 to 3, mayinclude the transistor TR1 that uses, as a channel CH1, a compoundsemiconductor nanowire 120 capable of greatly decreasing a short-channeleffect and decreasing power consumption. Accordingly, there may beprovided a next-generation integrated circuit device that may exceed,with a fast carrier movement rate, the limit of silicon semiconductors.Also, a gate length LG1 (refer to FIG. 1) that is precisely controlledin a self-alignment manner may be provided using a crystal phasesuperstructure in which ZB and WZ crystal phases are regularly arrangedin the compound semiconductor nanowire 120, and thus, a problem such asperformance degradation according to the distribution of gate lengths inthe integrated circuit devices 100 and 100A may be circumvented, andhigh reliability and performance may be realized.

FIG. 4 is a cross-sectional view of configurations of an integratedcircuit device 200 according to other embodiments of the inventiveconcepts. In FIG. 4, elements that are the same or similar as those inFIGS. 1 to 3 are designated by the same reference numerals, and repeateddescriptions thereof are omitted.

The integrated circuit device 200 illustrated in FIG. 4 generally hasthe same configuration as that of the integrated circuit device 100Aillustrated in FIG. 3, except that a gate dielectric layer 234 mayextend along an external side wall of the compound semiconductornanowire 120 while covering not only a side wall of the first section122 but also a side wall of each of the pair of second sections 126respectively connected to both ends of the first section 122, and anexternal side wall of a gate electrode GE2 may extend aligned with anexternal side wall of a portion of the gate dielectric layer 234 thatcovers the side wall of the second section 126.

Detailed configurations of the gate dielectric layer 234 and the gateelectrode GE2 are the same as described above regarding the gatedielectric layer 134 and the gate electrode GE1 with reference to FIGS.1 to 3.

The integrated circuit device 200 according to embodiments, describedwith reference to FIG. 4, may include a transistor TR2 that uses, as achannel CH1, a compound semiconductor nanowire 120 capable of greatlydecreasing a short-channel effect and decreasing power consumption.Accordingly, there may be provided a next-generation integrated circuitdevice that may exceed, with a fast carrier movement rate, the limit ofsilicon semiconductors. Also, a gate length LG2 that is preciselycontrolled in a self-alignment manner may be provided using a crystalphase superstructure in which ZB and WZ crystal phases are regularlyarranged in the compound semiconductor nanowire 120. Also, as the gatedielectric layer 234 extends along an external wall of the compoundsemiconductor nanowire 120 while covering from a side wall of the firstsection 122 to a side wall of each of the pair of second sections 126connected to both ends of the first section 122, the gate dielectriclayer 234 may serve as a barrier film between the wiring layer 150 andthe compound semiconductor nanowire 120. Accordingly, an undesiredreaction between the wiring layer 150, or a material thereof, and thecompound semiconductor nanowire 120 may be reduced or prevented fromtaking place while the wiring layer 150 is formed, and the integrationdensity of the integrated circuit device 200 may be improved.

FIG. 5 is a cross-sectional view of configurations of an integratedcircuit device 300 according to other embodiments of the inventiveconcepts. In FIG. 5, elements that are the same or similar as those inFIGS. 1 to 3 are designated by the same reference numerals, and repeateddescriptions thereof are omitted.

The integrated circuit device 300 illustrated in FIG. 5 generally hasthe same configuration as that of the integrated circuit device 100Aillustrated in FIG. 3. However, in the integrated circuit device 300,the pair of second sections 126 respectively adjoining both ends of thefirst section 122 may have a truncated shape portion 326T having adecreasing width so as to have a decreasing cross-section area towardthe first section 122 in an end portion of the respective ones of thepair of second sections 126 that adjoins the first section 122. Thetruncated shape portion 326T may have various shapes such as a truncatedcircular cone or a truncated hexagonal pyramid.

Also, in the integrated circuit device 300, a gate dielectric layer 334may extend covering not only a side wall of the first section 122 butalso a side wall of the truncated shape portion 326T of the respectiveones of the pair of second sections 126, and a gate electrode GE3 mayfill a surrounding space of the first section 122 between the pair ofsecond sections 126. In some embodiments, the gate electrode GE3 mayfill a space limited by the gate dielectric layer 334.

Detailed configuration of the gate dielectric layer 334 and the gateelectrode GE3 are the same or similar as described above regarding thegate dielectric layer 134 and the gate electrode GE1 with reference toFIGS. 1 to 3.

The integrated circuit device 300 according to embodiments of theinventive concepts, described with reference to FIG. 5, may include atransistor TR3 that uses, as a channel CH1, a compound semiconductornanowire 120 capable of greatly decreasing a short-channel effect anddecreasing power consumption. Accordingly, there may be provided anext-generation integrated circuit device that may exceed, with a fastcarrier movement rate, the limit of silicon semiconductors. Also, a gatelength LG3 that is precisely controlled in a self-alignment manner maybe provided using a crystal phase superstructure in which ZB and WZcrystal phases are regularly arranged in the compound semiconductornanowire 120. Further, an increased gate length LG3 may be providedusing the truncated shape portion 326T included in respective ones ofthe pair of second sections 126, and thus, performance of the transistorTR3 may be improved. Also, as the gate length LG3 increases, analignment margin between the wiring layer 150 and the gate electrode GE3may increase.

FIG. 6 is a cross-sectional view of configurations of an integratedcircuit device 400 according to other embodiments of the inventiveconcepts. In FIG. 6, elements that are the same or similar as those inFIGS. 1 to 5 are designated by the same reference numerals, and repeateddescriptions thereof are omitted.

The integrated circuit device 400 illustrated in FIG. 6 generally hasthe same or similar configuration as that of the integrated circuitdevice 200 illustrated in FIG. 4. However, in the integrated circuitdevice 400, the pair of second sections 126 respectively adjoining bothends of the first section 122 may have a truncated shape portion 426Thaving a decreasing width so as to have a decreasing cross-section areatoward the first section 122 in an end portion of the respective ones ofthe pair of second sections 126 that adjoins the first section 122. Thetruncated shape portion 426T may have various shapes such as a truncatedcircular cone or a truncated hexagonal pyramid.

Also, in the integrated circuit device 400, a gate dielectric layer 434may extend along an external wall of the compound semiconductor nanowire120 while covering not only a side wall of the first section 122 butalso a side wall of each of the pair of second sections 126 respectivelyconnected to both ends of the first section 122, and a gate electrodeGE4 may include a portion surrounding the first section 122 and aportion surrounding the truncated shape portion 426T. In addition, anexternal side wall of the gate electrode GE4 may extend aligned with anexternal side wall of a portion of the gate dielectric layer 434 thatcovers the side wall of the second section 126.

Detailed configurations of the gate dielectric layer 434 and the gateelectrode GE4 are the same or similar as described above regarding thegate dielectric layer 134 and the gate electrode GE1 with reference toFIGS. 1 to 3.

The integrated circuit device 400 according to embodiments, describedwith reference to FIG. 6, includes a transistor TR4 that uses, as achannel CH1, a compound semiconductor nanowire 120 capable of greatlydecreasing a short-channel effect and decreasing power consumption.Accordingly, there may be provided a next-generation integrated circuitdevice that may exceed, with a fast carrier movement rate, the limit ofsilicon semiconductors. Also, a gate length LG4 that is preciselycontrolled in a self-alignment manner may be provided using a crystalphase superstructure in which ZB and WZ crystal phases are regularlyarranged in the compound semiconductor nanowire. Also, an increased gatelength LG4 may be provided using the truncated shape portion 426Tincluded in the respective ones of the pair of second sections 126, andthus, performance of the transistor TR4 may be improved. Also, as thegate length LG4 increases, an alignment margin between the wiring layer150 and the gate electrode GE4 may increase. In addition, as the gatedielectric layer 434 extends on the compound semiconductor nanowire 120while covering from a side wall of the first section 122 to a side wallof each of the pair of second sections 126 connected to both ends of thefirst section 122, the gate dielectric layer 434 may serve as a barrierfilm between the wiring layer 150 and the compound semiconductornanowire 120. Accordingly, an undesired reaction between the wiringlayer 150 or a material thereof and the compound semiconductor nanowire120 may be reduced or prevented from taking place while the wiring layer150 is formed, and the integration density of the integrated circuitdevice 400 may be improved.

FIGS. 7A to 7C are diagrams of an integrated circuit device 500according to other embodiments of the inventive concepts, wherein FIG.7A is a layout of configurations of the integrated circuit device 500,FIG. 7B is a cross-sectional view taken along line B-B′ of FIG. 7A, andFIG. 7C is a cross-sectional view taken along line C-C′ of FIG. 7A. InFIGS. 7A to 7C, elements that are the same or similar as those in FIGS.1 to 3 are designated by the same reference numerals, and repeateddescriptions thereof are omitted.

Referring to FIGS. 7A to 7C, the integrated circuit device 500 mayinclude the substrate 110 having an active region AC defined by a deviceisolation film 502. The source region 110S is formed in the activeregion AC, and a surface of the source region 110S is covered with ametal silicide film 514. In some embodiments, the metal silicide film514 may include at least one metal selected from, for example, Ti, W,Ru, Nb, Mo, Hf, Ni, Co, Pt, Yb, Tb, Dy, Er, Pd, and a combinationthereof.

On the active region AC of the substrate 110, a plurality of compoundsemiconductor nanowires 120 may protrude in a first direction (e.g.,direction Z). Although FIG. 7A illustrates a case in which four compoundsemiconductor nanowires 120 (illustrated as TR1) are formed on oneactive region AC, the inventive concepts are not limited to theillustration in the accompanying drawing.

The gate dielectric layer 134 and the gate electrode GE1 that surroundthe first section 122 may be formed around the first section 122 of eachof the plurality of compound semiconductor nanowires 120.

The wiring layer 150 may extend parallel to the main surface 110M of thesubstrate 110 at the same level as that of the first section 122 of eachof the plurality of compound semiconductor nanowires 120. A plurality ofgate electrodes GE1 surrounding first sections 122 of the plurality ofcompound semiconductor nanowires 120 above the active region AC may beconnected to one wiring layer 150.

A first conductive contact plug 554 may be connected to the wiring layer150. The first conductive contact plug 554 may include a firstconductive barrier film 554A and a first conductive plug 554B. The firstconductive contact plug 554 may be used as a gate contact.

The first conductive barrier film 554A may include, for example, TiN,TaN, AlN, WN, or a combination thereof, and the first conductive plug554B may include, for example, W, Cu, Al, an alloy thereof, and/or acombination thereof. However, the inventive concepts are not limited tothe example materials.

A second conductive contact plug 556 may be connected to the sourceregion 110S. The second conductive contact plug 556 may include a secondconductive barrier film 556A and a second conductive plug 556B. Thesecond conductive contact plug 556 may be used as a source contact. Thesecond conductive barrier film 556A may include, for example, TiN, TaN,AlN, WN, or a combination thereof, and the second conductive plug 556Bmay include, for example, W, Cu, Al, an alloy thereof, and/or acombination thereof. However, the inventive concepts are not limited tothe example materials.

Each of the first conductive contact plug 554 and the second conductivecontact plug 556 may extend parallel to the plurality of compoundsemiconductor nanowires 120 in the first direction (e.g., direction Z).

The drain region 126D formed in the second section 126 of each of theplurality of compound semiconductor nanowires 120 may be connected to atop contact conductive layer 558. A plurality of drain regions 126D of aplurality of transistors TR1 formed on the one active region AC may beconnected to one top contact conductive layer 558. The top contactconductive layer 558 may be used as a drain contact. The top contactconductive layer 558 may include a top barrier film 558A and a topconductive film 558B. The top barrier film 558A may include, forexample, TiN, TaN, AlN, WN, or a combination thereof, and the topconductive film 558B may include, for example, W, Cu, Al, an alloythereof, and/or a combination thereof. However, the inventive conceptsare not limited to the example materials.

The top contact conductive layer 558 may penetrate an upper insulationlayer 540 covering the upper insulation spacer 152.

A horizontal width of the wiring layer 150, a horizontal width of theupper insulation spacer 152, and a horizontal width of the upperinsulation layer 540 may each be limited by a buried insulation layer560. As used herein, a horizontal width may be a width of a givenelement in a direction parallel to the substrate 110.

The first conductive contact plug 554 may extend in the first direction(e.g., direction Z) from the wiring layer 150, while penetrating theupper insulation spacer 152 and the upper insulation layer 540. Thesecond conductive contact plug 556 may extend in the first direction(e.g., direction Z), while penetrating the insulation mask layer 112,the lower insulation spacer 142, and the buried insulation layer 560,from the metal silicide film 514 formed on the surface of the sourceregion 110S.

Each of the upper insulation layer 540 and the buried insulation layer560 may include an oxide film, a nitride film, or a combination thereof,but a material of each of the upper insulation layer 540 and the buriedinsulation layer 560 is not limited thereto.

Next, methods of manufacturing integrated circuit devices according toembodiments will be described in detail.

FIGS. 8A to 8I are cross-sectional views illustrating methods ofmanufacturing integrated circuit devices according to embodiments of theinventive concepts. An example manufacturing method of the integratedcircuit device 100A illustrated in FIG. 3 will be described withreference to FIGS. 8A to 8I. In FIGS. 8A to 8I, elements that are thesame or similar as those in FIGS. 1 to 3 are designated by the samereference numerals, and repeated descriptions thereof are omitted.

Referring to FIG. 8A, the substrate 110 having the main surface 110Mthat is a {111} crystal plane is prepared, and the source region 110S isformed by injecting a first dopant into the substrate 110 from the mainsurface 110M of the substrate 110.

The first dopant may be variously selected according to a compositionmaterial of the substrate 110. Detailed configuration of the firstdopant may be understood from the descriptions made with reference toFIG. 1.

Afterwards, the insulation mask layer 112 having a hole 112H thatexposes the main surface 110M may be formed on the substrate 110.

Referring to FIG. 8B, the compound semiconductor nanowire 120 includinga Group III-V material may be grown from the main surface 110M of thesubstrate 110 that is exposed via the hole 112H.

The compound semiconductor nanowire 120 may be formed such that thefirst section 122 and the second section 126 having the same compositionas each other, but different crystal phases from each other, arealternately arranged in a first direction (e.g., direction Z). The firstsection 122 and the second section 126 may have different crystal phasesfrom each other, such as, for example, crystal phases selected from a ZBcrystal phase and a WZ crystal phase. In some embodiments, the firstsection 122 may have the WZ crystal phase, and the second section 126may have the ZB crystal phase. In some embodiments, the first section122 may have the ZB crystal phase, and the second section 126 may havethe WZ crystal phase. A length of each of the first section 122 and thesecond section 126 in the first direction (e.g., direction Z) may bevariously selected as necessary.

FIG. 8B illustrates a case in which the compound semiconductor nanowire120 includes one first section 122 above the substrate 110 and the pairof second sections 126 respectively adjoining both ends of the one firstsection 122 with the first section 122 in the middle. However, as markedwith a dashed line in FIG. 8B, the compound semiconductor nanowire 120may further include a dummy section 120D on the second section 126covering the first section 122. In some embodiments, the dummy section120D may include a material that has the same composition and the samecrystal phase as those of the first section 122. In some embodiments,the dummy section 120D may include a material that has the samecomposition and the same crystal phase as those of the second section126.

In some embodiments, an epitaxial growth process may be used to grow thecompound semiconductor nanowire 120. The epitaxial growth process mayinclude, for example, molecular beam epitaxy (MBE), metal-organic vaporphase epitaxy (MOVPE), metal-organic chemical vapor deposition (MOCVD),rapid thermal chemical vapor deposition (RTCVD), low-energy plasmadeposition (LEPD), ultra-high vacuum chemical vapor deposition (UHVCVD),or atmospheric pressure chemical vapor deposition (APCVD).

In some embodiments, process temperature, reaction gas, chamberpressure, etc. during the epitaxial growth process may be controlled todifferently control crystal phases of the first section 122 and thesecond section 126 constituting the compound semiconductor nanowire 120.

When the crystal phases of the first section 122 and the second section126 of the compound semiconductor nanowire 120 are differentlycontrolled using the process temperature during the epitaxial growthprocess, the first section 122 and the second section 126 may be grownwith the process temperature during epitaxial growth under differenttemperature conditions from each other. In some embodiments, thetemperature conditions may be selected from a range of about 400˜480° C.In some embodiments, when a temperature condition is selected from arelatively low temperature range within the range of about 400˜480° C.(e.g., a range of about 400˜420° C.), an InAs, InP, and/or GaAs nanowiresection that has the WZ crystal phase may be formed. In addition, when atemperature condition is selected from a relatively high temperaturerange within the range of about 400˜480° C. (e.g., a range of about450˜480° C.) an InAs, InP, or GaAs nanowire section that has the ZBcrystal phase may be formed. The above temperature ranges are justexamples, and various changes and modifications may be made thereinwithin the scope of the inventive concepts. For example, the processtemperature during epitaxial growth may be variously selected from arange of about 300˜550° C. As described above, nanowire sections havingdesired crystal phases may be formed to have a precisely controlledlength by properly changing the process temperature during the epitaxialgrowth process as desired.

The crystal phases of the first section 122 and the second section 126of the compound semiconductor nanowire 120 may be differently controlledusing process gas and pressure during the epitaxial growth process. Inthis case, the ZB crystal phase may be derived by further adding Zn, inaddition to source gases of a compound to be formed by epitaxial growth,and properly controlling pressure. For example, while the compoundsemiconductor nanowire 120 including InP or GaP is grown into the WZcrystal phase, the WZ crystal phase may be transitioned into the ZBcrystal phrase by supplying a sufficient amount of Zn together withsource gases for InP growth under a pressure of about 4.6×10⁻⁵ mbar. Inthis case, a section, from among the first section 122 and the secondsection 126 of the compound semiconductor nanowire 120, that has the ZBcrystal phase may have a structure doped with Zn. The above pressure isjust an example, and the inventive concepts are not limited thereto. Forexample, various pressure ranges selected from a range of about1×10⁻²˜1×10⁻⁷ mbar may be applied as necessary to differently controlthe crystal phases of the first section 122 and the second section 126of the compound semiconductor nanowire 120.

In another example of differently controlling the crystal phases of thefirst section 122 and the second section 126 of the compoundsemiconductor nanowire 120 by using the process gas during the epitaxialgrowth process, supply maintenance and supply cut-off of one of theprocess gases that are used during the epitaxial growth process may beselectively controlled. For example, while the compound semiconductornanowire 120 including a Group III-V material is grown, supplymaintenance and supply cut-off of a source gas of a Group III elementmay be repeatedly performed. While supply of the source gas of the GroupIII element is cut-off during the process of growing the compoundsemiconductor nanowire 120, stacking faults of a relatively high densitymay be formed in a direction perpendicular to a <111> growth direction.By regularly forming such stacking faults, the compound semiconductornanowire 120 having a crystal phase superstructure in which ZB and WZcrystal phases are regularly arranged may be obtained. For example, informing the compound semiconductor nanowire 120 including InAs, alow-pressure MOVPE (LP-MOVPE) process may be performed using the MOVPEsystem. In this regard, while an InAs nanowire having the ZB crystalphase is grown using trimethyl indium (TMI) as a source gas of the GroupIII element and using arsine (AsH₃) as a source gas of a Group V elementunder a process temperature of about 420˜460° C., supply of TMI may becut-off at a desired point of time, and the process temperature may belowered to about 380° C. to grow an InAs nanowire having the WZ crystalphase. As described above, nanowire sections having desired crystalphases may be formed to have a precisely controlled length by properlychanging an on-time and an off-time of source gas supply of the GroupIII element as desired.

Referring to FIG. 8C, a width of the first section 122 may be decreasedby selectively etching only the first section 122 from among the firstsection 122 and the second sections 126 in the compound semiconductornanowire 120, and at the same time, a space SP having a vertical lengthlimited by the pair of second sections 126 on both sides of the firstsection 122 having the decreased width may be prepared.

A difference in etch rates according to crystal phases may be used toselectively etch only the first section 122 from among the first section122 and the second sections 126. For example, etching using Piranhasolution, galvanic etching, or alkaline etching using ammoniumpolysulfide may be used to selectively etch only the first section 122from among the first section 122 and the second sections 126. However,the inventive concepts are not limited to the above examples.

When the dummy section 120D has the same crystal phase as that of thefirst section 122, a width of the dummy section 120D may also decreasetogether with a width of the first section 122 while the first section122 is selectively etched. Although only the one first section 122included in the compound semiconductor nanowire 120 is illustrated anddescribed in the present example, the inventive concepts are not limitedto the illustrations in the accompanying drawings.

Referring to FIG. 8D, a gate dielectric layer 135 covering an exposedsurface of the entire compound semiconductor nanowire 120 that includesa surface of the first section 122 having the decreased width (i.e., thesurface exposed via the space SP) is formed.

The gate dielectric layer 135 may include an interfacial layercontacting the first section 122, and a high-k dielectric layer coveringthe interfacial layer. The interfacial layer may be obtained byoxidizing the surface of the first section 122. The high-k dielectriclayer may be formed by an atomic layer deposition (ALD) or chemicalvapor deposition (CVD) process. The gate dielectric layer 134 may beformed to cover the exposed surface of the compound semiconductornanowire 120 in a uniform thickness.

Referring to FIG. 8E, a gate electrode forming conductive layer GEL isformed on the gate dielectric layer 135 to fill the space SP (refer toFIG. 8D) around the first section 122 having the decreased width.

The conductive layer GEL may include a work function controllingmetal-containing layer. In some embodiments, the conductive layer GELmay include a metal nitride layer or a metal layer. Each of the metalnitride layer and the metal layer may include at least one metalselected from, for example, Ti, W, Ru, Nb, Mo, Hf, Ni, Co, Pt, Yb, Tb,Dy, Er, and Pd. Each of the metal nitride layer and the metal layer maybe formed by an ALD, metal organic ALD (MOALD), or MOCVD process. Insome embodiments, the conductive layer GEL may include a stackedstructure of TiAlC/TiN, a stacked structure of TiN/TaN/TiAlC/TiN, or astacked structure of TiN/TaN/TiN/TiAlC/TiN.

Referring to FIG. 8F, by performing anisotropic dry etching on theconductive layer GEL and the gate dielectric layer 135 in aself-alignment manner using a shape of the compound semiconductornanowire 120, portions of the conductive layer GEL and the gatedielectric layer 135 that are at the outside of the space SP (refer toFIG. 8D) around the first section 122 having the decreased width areremoved to expose the top surface of the insulation mask layer 112 andside walls of the plurality of second sections 126. As a result, thegate electrode GE1 covering the gate dielectric layer 134 in the spaceSP may be obtained.

Referring to FIG. 8G, the lower insulation spacer 142 covering a sidewall of the second section 126 (from among the pair of second sections126 on both sides of the first section 122 surrounded by the gateelectrode GE1 around the compound semiconductor nanowire 120) that iscloser to the substrate 110, and covering a lower side portion of anexternal side wall of the gate electrode GE1, may be formed.

In some embodiments, in order to form the lower insulation spacer 142, afirst insulation layer covering the insulation mask layer 112 and thecompound semiconductor nanowire 120 may be formed, and, subsequently, aportion of the first insulation layer may be etched back so that thelower insulation spacer 142 illustrated in FIG. 8G may be left on theinsulation mask layer 112.

The lower insulation spacer 142 may include a material selected from,for example, SiN, SiCN, SiOCN, SiO₂, and a combination thereof, but amaterial of the lower insulation spacer 142 is not limited to the aboveexamples.

Referring to FIG. 8H, the wiring layer 150 covering, on the lowerinsulation spacer 142, a middle portion of the external side wall of thegate electrode GE1 may be formed.

The wiring layer 150 may be connected to the gate electrode GE1 and mayserve as a gate contact wiring layer. In forming the wiring layer 150, athickness of the wiring layer 150 may be determined such that each ofthe distance difference ΔD1 between a lowermost portion of the gateelectrode GE1 and a lowermost portion of the wiring layer 150 and thedistance difference ΔD2 between an uppermost portion of the gateelectrode GE1 and an uppermost portion of the wiring layer 150, in alength direction of the compound semiconductor nanowire 120 (e.g.,direction Z), may be greater than 0.

In order to form the wiring layer 150, a wiring forming conductive layercovering the lower insulation spacer 142 and the compound semiconductornanowire 120 may be formed. In some embodiments, the wiring formingconductive layer may include a metal layer. In some embodiments, thewiring forming conductive layer may have a stacked structure including aconductive barrier film and a metal layer. The conductive barrier filmmay include, for example, TiN, TaN, AlN, WN, or a combination thereof.The metal layer may include, for example, W, Cu, Al, an alloy thereof,and/or a combination thereof. However, composition materials of theconductive barrier film and the metal layer are not limited to the aboveexamples. After the wiring forming conductive layer is formed, a portionof the wiring forming conductive layer may be removed by etch-back sothat the wiring layer 150 illustrated in FIG. 8H may be left. While theportion of the wiring forming conductive layer is etched back, analignment margin between the wiring layer 150 and the gate electrode GE1may be further obtained at least as much as the distance difference ΔD2.Accordingly, during a process of forming the wiring layer 150, thethickness of the wiring layer 150 may be controlled in a state where arelatively big process margin is obtained, and thus, alignment precisionfor connection between the wiring layer 150 and the gate electrode GE1may be more easily obtained even without applying an overly strictprocess condition.

Referring to FIG. 8I, the upper insulation spacer 152 covering thewiring layer 150, an upper side portion of the external side wall of thegate electrode GE1, and a side wall of the second section 126 that isfarther from the substrate 110 (from among the pair of second sections126 on both sides of the first section 122 of the compound semiconductornanowire 120) may be formed.

In some embodiments, in order to form the upper insulation spacer 152, asecond insulation layer covering the wiring layer 150 and the compoundsemiconductor nanowire 120 may be formed, and, subsequently, aplanarization process may be performed on the second insulation layerand the compound semiconductor nanowire 120 until the second section126, from among the pair of second sections 126, that is farther fromthe substrate 110 is exposed. As a result, top surfaces of the upperinsulation spacer 152, which is a remaining portion of the secondinsulation layer, and the compound semiconductor nanowire 120 may extendon the same plane.

The upper insulation spacer 152 may include a material selected from,for example, SiN, SiCN, SiOCN, SiO₂, and a combination thereof, but amaterial of the upper insulation spacer 152 is not limited to the aboveexamples.

Afterwards, the drain region 126D is formed by implanting a seconddopant into the second section 126 that is exposed at the top surface ofthe compound semiconductor nanowire 120.

The second dopant may be variously selected according to a compositionmaterial of the compound semiconductor nanowire 120. Detailedconfiguration of the second dopant may be understood from thedescriptions made with reference to FIG. 1.

According to the method of manufacturing the integrated circuit device100A, described with reference to FIGS. 8A to 8I, a gate length that isprecisely controlled in a self-alignment manner may be provided using acrystal phase superstructure in which ZB and WZ crystal phases areregularly arranged in a compound semiconductor nanowire 120, and thus, aproblem such as performance degradation according to the distribution ofgate lengths in the integrated circuit device may be circumvented, andimproved reliability and performance may be realized. Also, in formingthe wiring layer 150 that is connected to the gate electrode GE1, arelatively big alignment margin between the wiring layer 150 and thegate electrode GE1 may be obtained, and thus, alignment precision forconnection between the wiring layer 150 and the gate electrode GE1 maybe more easily obtained even without applying an overly strict processcondition.

FIGS. 9A and 9B are cross-sectional views illustrating methods ofmanufacturing integrated circuits device according to other embodimentsof the inventive concepts. An example manufacturing method of theintegrated circuit device 200 illustrated in FIG. 4 will be describedwith reference to FIGS. 9A and 9B. In FIGS. 9A and 9B, elements that arethe same or similar as those in FIGS. 1 to 4 are designated by the samereference numerals, and repeated descriptions thereof are omitted.

Referring to FIG. 9A, the gate dielectric layer 135 covering thecompound semiconductor nanowire 120 and the gate electrode formingconductive layer GEL may be formed by performing the processes describedwith reference to FIGS. 8A to 8E, and, subsequently, anisotropic dryetching may be performed on the conductive layer GEL and the gatedielectric layer 135 as described above with reference to FIG. 8F.However, in the present example, the anisotropic dry etching process ofthe conductive layer GEL and the gate dielectric layer 135 may beperformed so that not only portions of the gate dielectric layer 135that are in the space SP around the first section 122 of the compoundsemiconductor nanowire 120, but also portions of the gate dielectriclayer 135 that cover an external side wall of the compound semiconductornanowire 120 (i.e., the external side wall including an external sidewall of the second section 126) may be left on the substrate 110.

As a result, as illustrated in FIG. 9A, the gate dielectric layer 234extending along an external wall of the compound semiconductor nanowire120 may be obtained from the gate dielectric layer 135 illustrated inFIG. 8E. Also, the gate electrode GE2 covering the first section 122 ofthe compound semiconductor nanowire 120 may be obtained from theconductive layer GEL illustrated in FIG. 8E. An external side wall ofthe gate electrode GE2 may be formed to extend aligned with an externalside wall of a portion of the gate dielectric layer 234 that covers aside wall of the second section 126.

Referring to FIG. 9B, the integrated circuit device 200 may be formed byperforming processes similar to those described with reference to FIGS.8G to 8I on a result of FIG. 9A.

Although example manufacturing methods of the integrated circuit devices100A and 200 illustrated in FIGS. 3 and 4 have been described above withreference to FIGS. 8A to 9B, it would be understood by one of ordinaryskill in the art that the integrated circuit devices 300 and 400illustrated in FIGS. 5 and 6 or integrated circuit devices of variousstructures that are modified and changed from the integrated circuitdevices 300 and 400 may be manufactured by incorporating variousmodifications and changes in the descriptions made with reference toFIGS. 8A to 9B within the scope of the inventive concepts.

In an example, in order to manufacture the integrated circuit device 300illustrated in FIG. 5, the processes described with reference to FIGS.8A to 8I may be performed.

However, during the process described with reference to FIG. 8C, inorder to prepare the space SP around the first section 122 having adecreased width, wherein the space SP has a vertical length limited bythe pair of second sections 126, while a portion of the first section122 is etched, an etch selectivity may be adjusted to remove an edgeportion of the pair of second sections 126 as well. As a result, as thespace SP is formed, a portion, from among the pair of second sections126 respectively adjoining both ends of the first section 122, that isadjacent to the first section 122 may be removed, and thus, thetruncated shape portion 326T having a decreasing width so as to have adecreasing cross-section area toward the first section 122 in an endportion of respective ones of the pair of second sections 126 thatadjoins the first section 122 may be left as illustrated in FIG. 5. Insome embodiments, after the space SP is formed, a horizontal width ofthe pair of second sections 126 may be minutely decreased. Afterwards,the integrated circuit device 300 having the structure illustrated inFIG. 5 may be manufactured by performing the processes described withreference to FIGS. 8D to 8I.

In another example, in order to manufacture the integrated circuitdevice 400 illustrated in FIG. 6, the processes described with referenceto FIGS. 9A and 9B may be performed. However, as in the manufacturingprocess of the integrated circuit device 300 having the structureillustrated in FIG. 5, during the process described with reference toFIG. 8C, in order to prepare the space SP around the first section 122having a decreased width, (wherein the space SP has a vertical lengthlimited by the pair of second sections 126), while a portion of thefirst section 122 is etched, an etch selectivity may be adjusted toremove an edge portion of the pair of second sections 126 as well. As aresult, as the space SP is formed, a portion, from among the pair ofsecond sections 126 respectively adjoining both ends of the firstsection 122, that is adjacent to the first section 122 may be removed,and thus, the truncated shape portion 426T having a decreasing width soas to have a decreasing cross-section area toward the first section 122in an end portion of respective ones of the pair of second sections 126that adjoins the first section 122 may be left as illustrated in FIG. 6.Afterwards, the integrated circuit device 400 having the structureillustrated in FIG. 6 may be manufactured by performing the processesdescribed with reference to FIGS. 8D to 8I and 9A to 9B.

FIGS. 10A to 15B are cross-sectional views illustrating methods ofmanufacturing integrated circuits device according to other embodimentsof the inventive concepts, wherein FIGS. 10A, 11A, . . . , 15A arecross-sectional views of a portion corresponding to a cross-sectiontaken along line B-B′ of FIG. 7A, and FIGS. 10B, 11B, . . . , 15B arecross-sectional views of a portion corresponding to a cross-sectiontaken along line C-C′ of FIG. 7A. A method of manufacturing theintegrated circuit device 500 illustrated in FIGS. 7A to 7C will bedescribed with reference to FIGS. 10A to 15B. In FIGS. 10A to 15B,elements that are the same or similar as those in FIGS. 1 to 9B aredesignated by the same reference numerals, and repeated descriptionsthereof are omitted.

Referring to FIGS. 10A and 10B, as described above with reference toFIG. 8A, the substrate 110 having the main surface 110M that is a {111}crystal plane may be prepared, and the source region 110S may be formedby implanting a first dopant into the substrate 110 from the mainsurface 110M of the substrate 110. Afterwards, the metal silicide film514 may be formed on the main surface 110M of the substrate 110.

Afterwards, a device isolating trench 502T for defining the activeregion AC may be formed by etching a partial region of the substrate110, and the device isolation film 502 may be formed by filling thedevice isolating trench 502T with an insulation layer.

Referring to FIGS. 11A and 11B, the insulation mask layer 112 includinga plurality of holes 112H may be formed on the substrate 110. In someembodiments, the plurality of holes 112H may extend through theinsulation mask layer 112 and the metal silicide film 514 to expose themain surface 110M of the substrate 110. Subsequently, as described abovewith reference to FIG. 8B, the plurality of compound semiconductornanowires 120 including Group III-V materials may be grown from the mainsurface 110M of the substrate 110 that is exposed via the plurality ofholes 112H.

Afterwards, processes similar to those described with reference to FIGS.8C to 8I may be performed on the plurality of compound semiconductornanowires 120, and thus, the gate dielectric layer 134 and the gateelectrode GE1 around the plurality of compound semiconductor nanowires120, which sequentially surround the first section 122, may be formed,the lower insulation spacer 142, the wiring layer 150, and the upperinsulation spacer 152 around the plurality of compound semiconductornanowires 120, which are sequentially stacked on the substrate 110, maybe formed, and the drain region 126D may be formed by implanting asecond dopant into the second section 126 that is exposed at the topsurface of each of the plurality of compound semiconductor nanowires120.

Referring to FIGS. 12A and 12B, the upper insulation layer 540 coveringthe upper insulation spacer 152 and the drain region 126D may be formedon a result of FIGS. 11A and 11B.

Referring to FIGS. 13A and 13B, a mask pattern 610 may be formed on theupper insulation layer 540, and then, using the mask pattern 610 as anetching mask, anisotropic dry etching may be performed on the upperinsulation layer 540, the upper insulation spacer 152, and the wiringlayer 150 sequentially to expose the lower insulation spacer 142. As aresult, a trench 612 that limits horizontal widths of the wiring layer150 and the upper insulation spacer 152 may be formed. The wiring layer150 remaining above the substrate 110 may contact the plurality of gateelectrodes GE1 while being around the plurality of compoundsemiconductor nanowires 120 and may extend parallel to the substrate 110while having a plane shape illustrated in FIG. 7A.

The mask pattern 610 may include, for example, a photoresist film, anoxide film, a nitride film, an oxynitride film, a polysilicon film, or acombination thereof.

While the upper insulation layer 540, the upper insulation spacer 152,and the wiring layer 150 are sequentially etched using the mask pattern610 as an etching mask, the lower insulation spacer 142 may be partiallyetched by over-etching.

Referring to FIGS. 14A and 14B, the mask pattern 610 (refer to FIGS. 13Aand 13B) may be removed, and then, the trench 612 around the wiringlayer 150 may be filled with an insulation material to form the buriedinsulation layer 560.

In some embodiments, in order to form the buried insulation layer 560,an insulation layer that covers the upper insulation layer 540 whilefilling the trench 612 in a thickness sufficient to fill the trench 612may be formed, and then, the insulation layer may be polished or etchedback, until the top surface of the upper insulation layer 540 isexposed, to obtain the buried insulation layer 560 having a planarizedtop surface. The top surface of the buried insulation layer 560 and thetop surface of the upper insulation layer 540 may extend on the samelevel. In some embodiments, the top surface of the buried insulationlayer 560 and the top surface of the upper insulation layer 540 may becoplanar.

Referring to FIGS. 15A and 15B, the first conductive contact plug 554that penetrates the upper insulation spacer 152 and the upper insulationlayer 540 and is connected to the wiring layer 150, the secondconductive contact plug 556 that penetrates the insulation mask layer112, the lower insulation spacer 142, and the buried insulation layer560 and is connected to the source region 110S via the metal silicidefilm 514, and the top contact conductive layer 558 that penetrates theupper insulation layer 540 and is connected to the drain region 126D maybe formed. As illustrated in FIG. 7A, one top contact conductive layer558 may be formed to cover all of the plurality of drain regions 126Dformed above one active region AC.

In some embodiments, the first conductive contact plug 554, the secondconductive contact plug 556, and the top contact conductive layer 558may be sequentially formed by separate photolithography processes,respectively. In some embodiments, at least two of the first conductivecontact plug 554, the second conductive contact plug 556, and the topcontact conductive layer 558 may be simultaneously formed by a singlephotolithography process.

Although methods of manufacturing example integrated circuit devicesaccording to embodiments of the inventive concepts have been describedabove with reference to FIGS. 8A to 15B, it would be understood by oneof ordinary skill in the art that integrated circuit devices of variousstructures that are modified and changed from the integrated circuitdevices described herein and illustrated in the accompanying drawingsmay be manufactured by incorporating various modifications and changesin the above descriptions within the scope of the inventive concepts.

Using methods of manufacturing integrated circuit devices according tothe inventive concepts, a gate length that is precisely controlled in aself-alignment manner may be provided using a crystal phasesuperstructure in which ZB and WZ crystal phases are regularly arrangedin a nanowire, and thus, a problem such as performance degradationaccording to the distribution of gate lengths in the integrated circuitdevice may be reduced or circumvented, and improved reliability andperformance may be realized. Also, in forming a wiring layer that isconnected to a gate electrode, a relatively big alignment margin betweenthe wiring layer and the gate electrode may be obtained, and thus,alignment precision for connection between the wiring layer and the gateelectrode may be more easily obtained even without applying an overlystrict process condition.

FIG. 16 is a block diagram of an electronic system 2000 including anintegrated circuit device according to embodiments of the inventiveconcepts.

The electronic system 2000 may include a controller 2010, aninput/output apparatus (I/O) 2020, a memory 2030, and an interface 2040,which may be connected to each other via a bus 2050.

The controller 2010 may include at least one of a microprocessor, adigital signal processor, and/or another similar processor. The I/O 2020may include at least one of a keypad, a keyboard, and/or a display. Thememory 2030 may be used to store a command executed by the controller2010. For example, the memory 2030 may be used to store user data.

The electronic system 2000 may configure a wireless communicationapparatus, or an apparatus capable of transmitting and/or receivinginformation in wireless settings. In order to transmit/receive data viaa wireless communication network in the electronic system 2000, theinterface 2040 may be configured as a wireless interface. The interface2040 may include an antenna and/or a wireless transceiver. In someembodiments, the electronic system 2000 may be used in a communicationinterface protocol of a third-generation communication system, forexample, code division multiple access (CDMA), global system for mobilecommunications (GSM), north American digital cellular (NADC),extended-time division multiple access (E-TDMA) and/or wide band codedivision multiple access (WCDMA). The electronic system 2000 includes atleast one of integrated circuit devices according to embodiments, forexample, the integrated circuit devices 100, 100A, 200, 300, 400, and500 illustrated in FIGS. 1 to 7C, and integrated circuit devices ofvarious structures that are modified and changed from the aforementionedintegrated circuit devices within the scope of the inventive concepts.

As used herein, the singular terms “a,” “an,” and “the” are intended toinclude the plural forms as well, unless the context clearly indicatesotherwise. It will be understood that when an element is referred to asbeing “connected” or “coupled” to another element, it may be directlyconnected or coupled to the other element or intervening elements may bepresent. As used herein, the term “and/or” includes any and allcombinations of one or more of the associated listed items. It will befurther understood that the terms “comprises,” “comprising,” “includes,”and/or “including,” when used herein, specify the presence of statedfeatures, integers, steps, operations, elements, and/or components, butdo not preclude the presence or addition of one or more other features,integers, steps, operations, elements, components, and/or groupsthereof.

Similarly, it will be understood that when an element such as a layer,region or substrate is referred to as being “on” another element, it canbe directly on the other element or intervening elements may be present.In contrast, the term “directly” means that there are no interveningelements. Additionally, the embodiments in the detailed description willbe described with sectional views as ideal example views of theinventive concepts.

Accordingly, shapes of the example views may be modified according tomanufacturing techniques and/or allowable errors. Therefore, theembodiments of the inventive concepts are not limited to the specificshape illustrated in the example views, but may include other shapesthat may be created according to manufacturing processes.

While such terms as “first,” “second,” etc., may be used to describevarious components, such components must not be limited to the aboveterms. The above terms are used only to distinguish one component fromanother. For example, a first component discussed below could be termeda second component, and similarly, a second component may be termed afirst component without departing from the teachings of this disclosure.

Spatially relative terms, such as “beneath,” “below,” “lower,” “above,”“upper,” and the like, may be used herein for ease of description todescribe one element or feature's relationship to another element(s) orfeature(s) as illustrated in the figures. It will be understood that thespatially relative terms are intended to encompass differentorientations of the device in use or operation in addition to theorientation depicted in the figures. For example, if the device in thefigures is turned over, elements described as “below” or “beneath” otherelements or features would then be oriented “above” the other elementsor features. Thus, the exemplary term “below” can encompass both anorientation of above and below. The device may be otherwise oriented(rotated 90 degrees or at other orientations) and the spatially relativedescriptors used herein interpreted accordingly.

Unless otherwise defined, all terms (including technical and scientificterms) used herein have the same meaning as commonly understood by oneof ordinary skill in the art to which these inventive concepts belong.It will be further understood that terms, such as those defined incommonly used dictionaries, should be interpreted as having a meaningthat is consistent with their meaning in the context of the relevant artand will not be interpreted in an idealized or overly formal senseunless expressly so defined herein.

Integrated circuit devices according to the inventive concepts mayinclude a transistor that uses, as a channel, a compound semiconductornanowire capable of greatly decreasing a short-channel effect and powerconsumption. Accordingly, there may be provided a next-generationintegrated circuit device that may exceed, with a fast carrier movementrate, the limit of silicon semiconductors. Also, a gate length that isprecisely controlled in a self-alignment manner may be provided using acrystal phase superstructure in which ZB and WZ crystal phases areregularly arranged in the compound semiconductor nanowire, and thus, aproblem such as performance degradation according to the distribution ofgate lengths in the integrated circuit device may be reduced orcircumvented, and improved reliability and performance may be realized.

While the inventive concepts have been particularly shown and describedwith reference to embodiments thereof, it will be understood thatvarious changes in form and details may be made therein withoutdeparting from the spirit and scope of the following claims.

1. An integrated circuit device comprising: a substrate comprising amain surface; a compound semiconductor nanowire extending from the mainsurface in a first direction perpendicular to the main surface andcomprising a first section and a second section alternately arranged inthe first direction, wherein the first section and the second sectionhave the same composition as each other and have different crystalphases from each other; a gate electrode covering the first section; anda gate dielectric layer between the first section and the gateelectrode.
 2. The integrated circuit device of claim 1, wherein thesubstrate comprises a Group IV material or a Group III-V material, andthe main surface has a {111} crystal plane.
 3. The integrated circuitdevice of claim 1, wherein the compound semiconductor nanowire comprisesa Group III-V material.
 4. The integrated circuit device of claim 1,wherein the compound semiconductor nanowire comprises at least one GroupIII element selected from indium (In), gallium (Ga), and aluminum (Al)and at least one Group V element selected from arsenic (As), phosphorus(P), and antimony (Sb), and the first section and the second sectionhave the different crystal phases respectively selected from azinc-blende (ZB) crystal phase and a wurtzite (WZ) crystal phase.
 5. Theintegrated circuit device of claim 1, wherein the compound semiconductornanowire comprises two second sections that are in a pair respectivelyadjoining both ends of the first section with the first section in themiddle, wherein the first section has a first width in a seconddirection parallel to the main surface of the substrate, and wherein thepair of second sections respectively have a second width in the seconddirection, wherein the second width is greater than the first width. 6.The integrated circuit device of claim 1, wherein the gate electrode hasan annular shape surrounding the first section.
 7. The integratedcircuit device of claim 1, further comprising: a source region in thesubstrate, the source region comprising a first dopant; and a drainregion in a portion of the compound semiconductor nanowire, the drainregion comprising a second dopant, wherein the first dopant and thesecond dopant comprise different elements from each other.
 8. Theintegrated circuit device of claim 7, wherein the drain region is in thesecond section.
 9. The integrated circuit device of claim 1, furthercomprising a wiring layer contacting the gate electrode and extendingparallel to the main surface of the substrate at a same level as that ofthe first section on the substrate.
 10. The integrated circuit device ofclaim 7, further comprising a conductive contact plug extending from thesource region in the first direction so as to be parallel to thecompound semiconductor nanowire. 11-15. (canceled)
 16. An integratedcircuit device comprising: a substrate comprising a main surface; acompound semiconductor nanowire extending from the main surface in afirst direction perpendicular to the main surface and comprising a lowersecond section, a first section on the lower second section, and anupper second section on the first section, wherein the first section hasa different crystal phase from the upper second section and the lowersecond section; a gate electrode on the first section, wherein a portionof the gate electrode is between, in the first direction, the uppersecond section and the lower second section.
 17. The integrated circuitdevice of claim 16, wherein the crystal phases of the first section, theupper second section, and the lower second section are selected from azinc-blende (ZB) crystal phase and a wurtzite (WZ) crystal phase. 18.The integrated circuit device of claim 16, further comprising a gatedielectric layer between the first section and the gate electrode andcovering sidewalls of the upper second section and the lower secondsection.
 19. The integrated circuit device of claim 16, furthercomprising a wiring layer contacting the gate electrode and extending ina direction that is substantially parallel to the main surface of thesubstrate and substantially perpendicular to the first section.
 20. Theintegrated circuit device of claim 16, wherein respective ends of theupper second section and the lower second section that are closest tothe first section have a truncated shape having a decreasing width so asto have a decreasing cross-section area toward the first section.